Metal pipe. Beware of robotic termites.
The item id for Pipe Metal in unturned is 1094. You can use this ID with the commands below to spawn the item, give it to a player or buy it on a modded economy server.
Useable: Barricade
Build: Freeform
Size_X: 1
Size_Y: 2
Size_Z: 0.475
Health: 1000
Range: 8
Radius: 0.25
Offset: 0.875
Explosion: 36
Blueprints: 1
Blueprint_0_Type: Barricade
Blueprint_0_Supplies: 1
Blueprint_0_Supply_0_ID: 67
Blueprint_0_Supply_0_Amount: 2
Blueprint_0_Build: 27
PlacementAudioClip: Sounds/MetalPlacement.mp3
Has_Clip_Prefab: false